Sliding vane rotary pump



Sept. 5, 1950 A. E. MCMANUS 2,521,592

sunmc VANE ROTARY PUMP Filed Dec. 29, 1945 4 Sheets-Sheet 1 a O I I as 656 I a 49 2 J O O 1 3 u a 0 o mun-u. 48 1 W6. Ila-m f: I By W Sept. 5, 1950 4 Sheets-$heet 5 Filed Dec. 29. 1945 MIKE/V702 Sept. 5, 1950 A. E. MCMANUS 2,521,592

' SLIDING VANE ROTARY PUMP Filed Dec. 29. 1945 4 Sheets-Sheet 4 IN V EN TOR.

WZIY/QM 63 a. 60W

arme/vsv Patented Sept. 1950 UNITED STATES PATENT OFFICE SLIDING VAN E ROTARY PUMP Albert E. McManus, Los Angeles, Calif.

Application December 29, 1945, Serial No. 638,115

13 Claims. (Cl. 103-123) This invention relates to a vane type pump.

It is an object of this invention to provide a pump of this type capable of operating at high speed and of handling large amounts of fluid, which is of light weight and which may be fabricated in an inexpensive manner.

It is another object of this invention to provide a vane type pump of a balanced design, so that no radial load is imposed on the rotating parts by the pressure of the fluid handled.

It is another object of this invention to provide a vane type pump capable of operation in either direction.

It is another object of this invention to provide such a pump wherein there is no centrifugal force acting on the vanes.

It is another object of this invention to provide such a pump in which the force acting to urge the vanes to sealing relation is substantially constant for all positions of the vanes and independent of the speed of the pump.

It is still another object of this invention to provide a vane type pump which is adapted without alteration to handle liquid or gases.

It is still another object of this invention to provide a vane type pump in which there is no knock caused by fluid locked in the pump.

It is still another object of this invention to provide a vane type pump in which pulsations in the output are substantially reduced.

It is still another object of this invention to provide such a pump having large chambers for cooling fluid.

It is still another object of this invention to provide such a pump adapted to have the major parts formed by assembling and joining suitable stampings of sheet stock, or of sheet stock and tubing.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of one embodiment of the invention. For this purpose there is shown a form in the drawings accompanying and forming part of the present specification. This form will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

In the drawings:

Figure 1 is a side elevation of a pump incorporating the features of the invention;

Figure 2 is an end elevation, as seen from the left in Figure 1;

Figure 3 is a fragmentary section on an en- 2 larged scale, taken as indicated by line 33 of Figure 2;

Figure 4 is a fragmentary cross section, taken as indicated by line 4-6 of Figure 3;

Figure 5 is a cross section partly in elevation, taken as indicated by line 5-5 of Figure 3, on a reduced scale;

Figure 6 is a fragmentary cross section taken as indicated by line 6-6 of Figure 4;

Figure 7 is a fragmentary cross section on an enlarged scale, taken as indicated by line 'I'| on Figure 6;

Figure 8 is a pictorial view illustrating the manner of fabricating one of the pump stators;

Figures 9 and 10 are diagrams, useful in explaining the operation of the pump; and,

Figures 11 and 12 are cross sections taken substantially as indicated by the correspondingly numbered lines on Figure 3, and partly broken away to show the structure.

The pump is of that type wherein a pair of relatively rotatable members provide opposed eccentric surfaces, the distance between which at a given point varies in accordance with the rotation of the members, one of said members carrying one or more vanes radially movable to contact the surface of the other member and divide the space between the surfaces into pockets. Appropriate inlet and outlet ports are provided for the space. Thus, as the capacity of a pocket increases as the surfaces separate due to rotation of the member, .fluid enters through the inlet. As the capacity of the pocket decreases due to the surfaces approaching each other, fluid is discharged through the outlet.

In the present instance, one of the members provides a pair of cylindrical surfaces forming an annular space. The other member of ring like form is disposed in this space, the opposite sides of the ring providing surfaces which are eccentric with respect to the cylindrical surfaces. The member providing the cylindrical surfaces is provided with a plurality of vanes adapted to contact respectively the opposite surfaces of the ring-like member. Thus, a plurality of pockets are provided on opposite sides thereof, which vary in capacity in response to relative rotation between the members, as above pointed out.

Referring to the drawings, the pump comprises a casing l providing a pair of stators 2 and 3, and enclosing and rotatably supporting the rotor 4. The casing l comprises an external cylindrical member ill to which is secured intermediate the ends thereof a central ring ll (see Figures 3, 4 and 8) provided with angularly spaced radial slots l2 extending from the inner periph- 3 ery. Transversely extending radial pairs of spaced plates l3 and I4 are secured to the rin II respectively on opposite sides of each slot i2. Each plate l3 and I4 has a slot l3a, l4a into which the ring H fits, the plates l3, l4 extending beyond the outer periphery of ring II where they are accommodated in grooves I 3 in the outer member ll (see Figure 4). Cylindrical segments ii are fitted between the projecting inner ends of adjacent pairs of plates I3 and I4 at the inner periphery of the ring ll. Circular segments I! are positioned between the outer ends of adjacent pairs of plates l3 and I4, and between the member l3 and segments l3, cooperating to form an outer ring spaced axially from the central ring ll. Segments l3 similarly form a ring onthe opposite side of the ring H. The assembly just described is secured together in a fluid tight manner by any suitable means, for example as by oven brazing, forming the outer stator 2. As clearly shown in the drawings, all of the pieces ll, I3, l4, l3 and II are adaptedto be formed of plate material, as by a stamping operation.

The inner stator 3 is built up from plate materials in a similar way on a central stub shaft or tubular member 23 (see Figures 3 and 4). Thus, there is a central ring 2| having slots 22 extending radially from the outer periphery,

with transverse radial pairs of plates 23 and 24 secured therein, the inner ends of plates 23 and 24 being accommodated in grooves 23 in the member 23. Cylindrical segments 23 are provided on the outer periphery of the ring 2| between adjacent pairs of transverse plates 23 and 24, and circular segments 21 are provided between se ments 26 and member 2! and between the outer ends of said pairs of plates. The segments 21 cooperate in a manner similar to segments I1, and form a ring on one side of the central ring 2i, segments 23 forming a ring on the opposite side. The assembly is secured together in a fluid tight manner as before, for example by a brazing process.

The outer and inner stators 2 and 3 are secured in assembled relation by means of a manifold structure 33 (Figure 3), which is secured against a shoulder 23-41 on the central member 23, and is restrained from rotating thereon as by a key 3|. The outer member l3 carryin the stator 2 is secured to the manifold 33 by a number of bolts 32.

When assembled, the cylindrical segmental plates i3 and 23 provide surfaces curved about the axis of rotation 3 of the rotor structure 4, to provide a space 3 in which a ring like portion 33 of the rotor 4 revolves. Furthermore, the exterior surfaces of the plates or outer rings formed respectively by the segments l1 and 21, and by the segments [3 and 23 are aligned.

The rotor 4 comprises a pair of spaced circular plates 34 and 33 between which the ring like portion 33 extends. Plate 33 is rotatably mounted on the central member 23 near its outer end, plate 34 being rotatably supported on the inner end of the member 23 and secured to a drivin shaft 36 by which the rotor 4 may be driven.

A manifold structure 31, similar to the manifold 33, is secured on the opposite end of the member II as by bolts 33 and provides a bearin 33 for the shaft 33. A suitable packin means 43 prevents leakage along the shaft. The member l3 has a greater axial length than the stators 2 and 3. The arrangement is such that when assembled these stators provide a space 4! between the face 42 of manifold 33 and the face of surface of ring portion 33.

plates I3 and 23 for accommodating the rotor plate 33 and a similar space 43 between the face 44 of manifold 31 and the face of plates I1 and 21 for accommodating the rotor plate 34.

The ring like portion 33 of the rotor 4 extends between the plates 34 and 33 through the space 3 defined between the stators dividing the space into outer and inner fluid spaces 3-a and 3-b. As clearly shown in Figures 4 and 5, the ring like portion 33 is non-circular with respect to its axis of rotation 3, thus, when the rotor revolves the opposite surfaces of the ring move toward and away from the stator surfaces defining the space 3.

To cause such movement to create a pumping action, the spaces 3a and 3-D are each divided into a plurality of pockets 43 and 41, by vanes or blades 43 and 43 slidingly accommodated in the spaces between the transverse plates l3|4, and 2324. and urged to seal respectively against the opposite surfaces of the ring 33. Spring means are provided for resiliently urging the vanes 43 and 49 to sealing relation, and means are provided for maintaining the springs under substantially constant tension.

Thus, referring to Figures 6 and 7, each outer corner of the vanes 43 are recessed at 33 to accommodatea shoe 3| having a head 32 for confining a compression spring 33 against a shoulder 34 on the vane. As shown in Figure 7, the leg 33 of the shoe has a recess 33a for confining the spring 33 in one plane, the spring being confined in a plane at right angles thereto between the inside of the leg 33 and the face 53-11 of the recess 33.

To appropriately tension the springs 33, earns 33 and 33 are provided on the rotor plates 34 and 33 respectively for engaging the shoes 3|. These cams 33 and 33, as clearly indicated in Figure 5, have configurations similar to the outer Thus, as this surface moves away from the stator 2, at any given point, the vanes 43 adjacent thereto are caused to move toward the surface by the earns 33 and 33; when the surface moves away from the stator, the earns 33 and 33 allow the vanes to move outwardly. It will be understood that theparts are so proportioned that shoes 3| act on the vanes 43 only through the springs 33, the cams 53 and 39 serving to maintain the force exerted by these springs substantially constant for all positions of the vanes. Circular recesses ll-a and "I3a are provided about the stator 2 for accommodating earns 33 and 33.

The vanes 43 of the inner stator 3 are similarly arranged to be urged resiliently against the inner surface of ring portion 33, being provided with shoes SI for this purpose, engaging earns 32 and 33, which have the same configuration as the inner surface of the ring portion 33.

As the rotor 4 rotates, the pockets 43 and 41 increase and decrease in volume cyclically. Thus, by providing an inlet to the pockets when their volume is increasing and an outlet when their volume is decreasing, a pumping action may be provided. For this purpose the rotor plate 34 is provided with a pair of oppositely disposed arcuate ports 34-a and 34-!) of limited angular extent, the rotor plate 33 being provided with a similar pair of ports 63a and 33-b, disposed at 90 with respect to ports 34-41 and 34-h (see Figures 9, 10, 11 and 12). The ports 34-a and 34-h serve as inlet ports, the ports 33-a and 33-h serving as outlet ports, being caused to communicate with the appropriate pockets 43 in the outer space 6--q by the valving action of the vanes 48, as the ports are swept past the vanes 48 by the rotation of the rotor 4. Similarly, inlet ports 14-41 and ||I4-'b are provided in plate 34, and outletports Ii-a and Iii-11 are provided in plate 35, for the pockets 41 in the inner space 6b, being controlled by the blades 49. The manifold structure 31 forms the intake manifold, for which purpose the innerplate I31 thereof, which contacts plate 34, is provided with an annular opening I38 overlying the inlet ports 64a, 64-h, |04-a and ||l4b. The structure 30 then forms the outlet manifold, the plate 16 thereof which contacts the plate 35 having an annular opening |3| overlying the outlet ports |04-a, ||l4--b, 105-11 and ||l5--b.

To provide a mechanically balanced rotor as well as to improve the pumping action, the rotor 4 is made symmetrical about the axis 5. Thus, as shown in Figures 4, 5, 9 and 10, the ring-like portion 33 is made of oval form to provide a pair of diametrically opposite lobes 33-a and 33-h. In this way, diametrically opposite pockets 41 within the ring portion 33 are under identical pressure conditions. Similarly diametrically opposite pockets 46 without the ring portion 33 are also under identical pressure conditions. Thus the fluid pressure on the rotor is always balanced, and the capacity of the pump is increased. Further, since the outerpockets 41 are at right angles with the inner pockets 46 under corresponding pressure conditions, the output is more nearly constant.

The operation of the pump is best explained in connection with the diagrams, Figures 9 and 10, wherein the vanes 48 and 49 are indicated by single lines and for clarity both the inlet and outlet ports are shown although actually only one or the other set of ports would be visible, the inlet ports being indicated by cross hatching inclined toward the right, the outlet ports being indicated by cross hatching inclined toward the left. Referring to Figure 9, with the rotor ring 33 rotating clockwise, the outer surface of the ring in the upper righthand and the lower left hand quadrants of the figure, will be moving inwardly, causing pockets 46 in those quadrants to increase in volume, and liquid to be drawn into them through the intakes 64a and 64-h. In the other two quadrants, the outer surface of the rotor ring 33 will be moving outwardly forcing fluid from the pockets 46 in stator.

these quadrants through the outlet ports 65-a and 65b.

Movement of the rotor 4 will cause the ports 64a and 64-b, and 65a and 65-h to sweep past the vanes 48, so that those pockets formerly connected with the inlet ports will be connected to the outlet ports and vice versa. Thus, after 90 rotation of the rotor 4 conditions will be as shown in Figure 10. Therein, the size of the pockets in the upper right hand and the lower left hand quadrants is decreasing and fluid is being discharged therefrom through the ports 65b and 65-11 which are now positioned to communicate with them. Similarly, fluid is now being drawn into the pockets in the other quadrants since the ring surface therein is moving inwardly, ports 64-a and 64-h now being in the appropriate positions. 7

The operations of fluid intake and. discharge by the pockets within the rotor ring 33 through ports ||l4-a and ||l4-b and ||l5a, ||l5-b respectively, are exactly the same as just described but differ therefrom by a 90 movement of the The chambers 10, 1| and 12, 13, Figures 3 and 4 which are formed in the stator members I and 3 as an incident to their method of fabrication, are well adapted for the circulation of a coolant fluid should such be desirable. For this purpose,

.each pair of chambers .10 and 1| is placed in communication by suitable apertures 14 through the center ring Similarly, each pair of chambers 12 and 13 communicates through aperture 15 in ring,2|..

The manifold structure 30 is built up of a pair of circular plates 16 and 11 secured in spaced re lation by a plurality of concentric rings 18, 18 and 80, and a base member 8|. and provide a space 82 in the manifold for receiving the discharge from ports 65-11 and 65-h, and |05-a and IDS-b and leading it to a common outlet 83. The rings 18 and 19 form a chamber 84 for leading coolant from an inlet 85 to a plurality of ports 86 in the member |8, each of which communicates with a pocket 18. The ring 80 and the base 8l'form a chamber 81 which may be used for lubricant, the lubricant being fed through suitable ducts, one of which is shown at 88, to the relatively rotating surfaces. The chamber 81 may be supplied with lubricant by suitable means (not shown).

The manifold structure 31 is quite similar, being arranged to provide a chamber 90 for distributing fluid from an inlet 9| to the inlet ports 64-41 and 64b, and |04-a and |04b, a coolant chamber 92 into which the ports 93 from the chambers 1| open and having an outlet 94, and a lubricant chamber 95. The central member 20 is provided with a plurality of ports 96 leading from a common inlet 91 to chambers 12, and a common outlet 99 into which ports 98 from spaces 13 open, for coolantflow.

I claim:

1. In a vane pump: a pair of relatively rotatable members having opposed surfaces curved about the axis of rotation and providing a fluid space between the members, a plurality of vanes carried by one of said members for movement in a generally radial direction with respect to said axis to cause their edges to seal against the surface of the other member, whereby said space is divided into a plurality of fluid tight pockets, means providing a cam face, consistently curved with respect to the surface of said other member about said axis and spaced radially from said surface of the other member, said cam face engaging said vanes opposite said sealing edges to maintain said vanes in sealing relation with said surface, said means extending across the ends of said space and sealing against said vanes, and having openings controlled by said vanes in accordance with the relative rotation between said members, to form inlet and outlet ports for said pockets.

2. In a vane pump: a pair of relatively rotatable members having opposed surfaces curved about the axis of rotation and providing a fluid space between the members, a plurality of vanes carried by one of said members for movement in a generally radial direction with respect to said axis to cause their edges to seal against the surface of the other member, whereby said space is divided into a plurality of fluid tight pockets,

The rings 13- 7 meansproviding a cam face, consistently curved with respect to the surface of said other member about said axis and spaced radially from said surface of the other member, means interposed between said cam face and said vanes resiliently urging said sealing edges toward said surface, and means adapted to form inlet and outlet ports for said pockets, said last mentioned means extending across the ends of said space and sealing against said vanes, and having openings controlled by said vanes in accordance with the relative rotation between said members.

3. In a vane pump: a pair of relatively rotatable members having opposed surfaces curved about the axis of rotation and providing fluid space between the members, a plurality of vanes carried by one of said members for movement in a generally radial direction with respect to said axis to seal against the surface of the other member and divide said space into a plurality of fluid tight pockets, spring means urging said vanes against said surface of the other member, means maintaining the force exerted by said springs substantially constant, comprising a cam having a configuration substantially identical with said surface, and means providing inlet and outlet ports for said pockets, said last mentioned means extending across the ends of said space and sealing against said vanes, and having openings controlled by said vanes in accordance with the relative rotation between said members.

4. In a vane pump: a pair of relatively rotatable members, one of said members having a pair of radially spaced surfaces curved about the axis of rotation provided a space extending about said axis, the other of said members having a ring-like portion accommodated in said space, the opposite surfaces thereof being correspondingly curved and so curved as to cooperate respectively with said first mentioned surfaces to provide a pair of fluid spaces on opposite sides of said ring-like portion, radially movable vanes carried by said one member for engaging the opposite surfaces of said ring like portion and dividing each space into a plurality of fluid tight pockets, the size of which varies in response to relative rotation between the members; means adapted to form inlet and outlet ports for said pockets respectively in accordance with increase and decrease of size thereof; cam means spaced radially inwardly and outwardly of the surfaces of said ring-like portion, and of a configuration corresponding respectively to said surfaces; and means whereby said cam means maintains the vanes in sealing relation with their respective surfaces.

5. In a vane pump: a pair of relatively rotatable members, said members having opposed surfaces curved about the axis of rotation and providing a fluid space between the members, the curvature of one surface gdiifering from that of the other surface, a plura ity of radially extending vanes sealing between said surfaces, whereby said fluid space is divided into a plurality of fluid tight pockets which vary in size in accordance with the relative rotation of the members, means forming inlet and outlet ports for said pockets, and means forming chambers for coolant fluid extending about said axis inwardly and outwardly of said space.

6. In a vane pump: a pair of relatively rotatable members, said members having opposed surfaces curved about the axis of rotation and providing a fluid space between the members, the curvature of one surface differing from that of 8 the other surface, a plurality of radially extending vanes sealing between said surfaces, whereby said fluid space is divided into a plurality of fluid tight pockets which vary in size in accordance with the relative rotation of the members, a pair of plates closing respectively the opposite ends of said space, ports in said plates forming respectively inlets and outlets for said pockets and controlled -by said vanes in response to relative movement between the members, means forming a manifold, for connecting the ports of each plate, and means forming chambers for coolant fluid extending about said axis inwardly and outwardly of said space.

7. A built up pump element for a vane pump, comprising a center ring, an outer ring spaced axially on each side thereof, cylindrical members connecting respectively the inner and outer peripheries of said rings, angularly spaced pairs of parallel plates extending between said outer rings and between said members, one of said members being grooved to accommodate the ends of said plates, the other member as well as said outer rings having through openings for accommodating the plates as a pair, said center ring having slots extending from that periphery opposite the grooved member part way to the other periphery for accommodating said plates as a pair, said rings, said plates and said members being joined in a fluid tight manner.

8. A bulit-up pump element for a vane pump,

comprising a center ring having angularly spaced radial slots extending from one periphery of said ring for accommodating the vanes, pairs of transverse, spaced radial plates on opposite sides respectively of said slots for guiding the vanes, and extending beyond each periphery of the ring, a cylindrical member extending entirely about one periphery of the ring having an axial length exceeding that of said plates and being slotted to receive the plates, cylindrical segments extending between adjacent pairs of plates along the other periphery of the ring, and circular seg ments also extending between adjacent pairs of plates as well as between the corresponding cylindrical segment and said member, said member, said plates and said segments being joined in a fluid tight manner.

9. In a vane pump: a stationary member having a pair of opposed curved surfaces providing a fluid space; a rotatable member, comprising a ring-like element having inner and outer surfaces differently curved than the respective surfaces of the stationary member and dividing said space into fluid chambers; a plurality of angularly spaced radially directed vanes carried by said stationary member for movement to engage respectively the surfaces of said rotatable member, said vanes sealing between said members to form fluid tight pockets varying in volume in accordance with the rotation of said rotatable member; said rotatable member including end elements secured to the opposite ends of said ring-like element for rotation therewith to seal said spaces and having angularly spaced ports cooperating with said vanes to form inlets for said pockets when increasing in size as well as angularly spaced ports cooperatin with said vanes to form outlets for said pockets when decreasing in size; and means carried by said end elements maintaing said vanes in contact with the surfaces of the ring-like element.

10. In a vane pump: a stationary member, comprising a pair of spaced curved cylindrical elements cooperating to provide a, fluid space, and inner and outer members joined in radially spaced relation to said elements providing spaces extending about said fluid space; a rotatable member having a ring-like element in said fluid space differently curved than said elements and dividing said fluid space into fluid chambers; means formin a plurality of angularly spaced radially directed guides extending respectively between the inner cylindrical element and the inner member, and between the outer cylindrical element and the outer member and dividing said spaces into segments; a radial wall dividing each segment into a pair of coolant chambers; and permitting limited communication therebetween; vanes slidingly accommodated in said guides for sealing respectively against the surfaces of said ring-like element, dividing the fluid space into a plurality of fluid tight pockets varying in size in accordance with the rotation of the rotatable member; means forming inlet and outlet ports for said pockets; and means forming a fluid passage connecting corresponding coolant chambers of each pair.

11. In a vane pump: a stationary member, comprising a pair of spaced curved cylindrical elements cooperating to provide a fluid space, and inner and outer members joined in radially spaced relation to said elements providing spaces extending about said fluid space; a rotatable member having a ring-like element in said fluid space diflerently curved than said elements and dividing said fluid space into fluid chambers; means forming a plurality of angularly spaced radially directed guides extending respectively between the inner cylindrical element and the inner member, and between the outer cylindrical element and the outer member and dividing said spaces into segments; a radial wall dividing each segment into a pair of coolant chambers; and permitting limited communication therebetween; vanes slidingly accommodated in said guides for sealing respectively against the surfaces of said ring-like element, dividing the fluid space into a plurality of fluid tight pockets varying in size in accordance with the rotation of the rotatable member; said rotatable member including end elements secured to the opposite ends of said ring-like element for rotation therewith to seal said spaces, and having angularly spaced ports, the ports in one end element cooperating with said vanes to form inlets for said pockets when increasing in size, the ports in the other end element cooperating with said vanes to form outlets for said pockets when decreasing in size; means forming manifolds connecting respectively the ports in each end element, said manifolds also providing respectively fluid passages for connecting corresponding coolant chambers of each of said pairs.

12. In a vane pump: a stationary member having a pair of coaxial opposed spaced cylindrical surfaces; a rotatable member comprising a ringlike element accommodated in the space between said surfaces and having a plurality of oppositely directed lobes dividing said space into a plurality of substantially equal fluid chambers on opposite sides of the element; a plurality of angularly spaced radially directed vanes sealing respectively between said element and said surfaces to divide said chambers into a'plurality of fluid tight pockets, said pockets varying in volume in accordance with the rotation of the rotatable member; and means carried 'by said element and having openings for cooperating with said vanes to form inlet ports for these pockets increasing volume and to form outlet ports for those pockets decreasing in volume, the oppositely directed lobes causing corresponding pressure conditions in pockets disposed at right angles and on opposite sides of said element. whereby a more nearly constant out-put is provided. t

13. In a vane pump: a stationary member having a pair of opposed, spaced curved surfaces providing a fluid space; a rotatable member comprising a ring-like element dividing said space into fluid chambers and having inner and outer surfaces differently curved than the surfaces of the stationary member, and a plurality of angularly spaced radially movable blades mounted by said stationary member, respectively sealing against the opposite surfaces of said element.

' ALBERT E. McMANUS.

REFERENCES CITED The following references are of record in the file of this patent:

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